Tesla has decided to install a “dummy” camera in its new vehicles equipped with its Hardware 4.0 Autopilot/Self-Driving sensors.

Hardware 4.0 is Tesla’s latest suite of sensors and computer that powers its Autopilot and Full Self-Driving package features. We have been gradually learning more about the new sensors and computer over the last few months.

We learned that the automaker is changing its cameras, according to a filing with Chinese regulators. More specifically, the filing showed that Tesla has changed its front-facing camera setup from three to two cameras.

This was later confirmed by a teardown of this new Hardware 4.0 computer.

But we were confused when we started to see the first Model S and Model X vehicles coming out of the Fremont Factory. They had a new front-facing camera enclosure, but it looked like it still had three cameras.

Now we learn why, thanks to the first service manuals for the new Model S and Model X being built with Hardware 4.0.

It gives us a closer look where we can see that the camera on the left is different, almost looking like a dud:

It could have been a different sensor, but in the manual, Tesla confirms that it is a dummy camera:

The bi-camera assembly has cutouts for 3 camera lens assemblies, but one of the cutout is populated with a dummy camera.

Here it is:

Tesla doesn’t explain why it put a dummy camera in the cutout, but the computer teardown did reveal that Tesla had one “spare” camera input in the new Hardware 4.0 computer.

It could be that Tesla is planning to install a new camera later, but it’s not clear why it needs to put a fake one in the meantime.

Tesla is starting to deliver its first vehicles with Hardware 4.0 starting with new Model S and Model X vehicles. Model 3 and Model Y are expected to follow.